1. Field of the Invention
The present invention relates to a composition containing a δ-aminolevulinic acid as effective dose for prevention and treatment of infection by pathogenic microorganisms and parasite. More specifically it refers to the composition for prevention and treatment through cultivation of fish in a water tank containing δ-aminolevulinic acid or the oral administration of a feed mixed with δ-aminolevulinic acid to fish.
2. Description of the Prior Art
Recently, with the technical development of artificial seedling production of fish, the cultivation industry is rapidly increasing. Thus, high quality fish such as a flatfish (Paralichyhus olivaceus), rockfish (Sebastes schoegeli Hilgendorf), Red seabream (Pagrus major), a swellfish are in the spotlight as cultivation fish. Due to this rapid expansion of the cultivation industry, the environment, such as the Korean coastal seawaters, are always in danger of generating diseases with the probability that it could be polluted by pathological bacteria such as Herpesvirus, Birnavirus, Rhabdovirus, which are main pathological viruses and Edwardsiella sp., Vibrio sp., Staphylococcus sp., Streptococcus, Flexibacter sp., which are pathological bacteria. (Cheung, R. J., Nigrelli, R. F. and Ruggieri, G. D. 1980. Studies on the morphology of uronema with a description of the infection in marine fish, J. Fish Disease, 3; 295; Drolet M., Peloguin L., Escelard Y., Cousineau L., and Sasarman A., 1989. Isolation and nucleotide sequence of the hemA gene of E. coli K-12, Mol. Gen. Genet, 216; 347: Ellen, N. L, and Kaplan S., 1993. 5-Aminolevulinic acid availability and control of spectral complex formation in hemA and hemT mutant of R. spharoides, J. Bacteriol., 175; 2304) and the cultivating industry have been seriously damaged by this pathological infection. Damage caused by pathological bacteria and virus infections of seedling production is worse than that of adult fish cultivation, which also has been increasing yearly. For the prevention and treatment of these bacterial diseases, antibiotics for veterinary use have been currently applied. Over-administration of improper antibiotics in an attempt to cure the diseases caused by unidentified pathological bacteria increases the cost of cultivating fish. It may also result in the emergence of bacteria having new tolerances because of the new antibiotics, and thereby delaying the experimental time and preventing prompt treatments. Accordingly, feed supplement for increasing the vitality or immunity of cultivating fish has been in development since the mass mortality rate of cultivating fish is increasing.
As explained above, among the marine fish diseases attacking in Korea, besides microorganism and viruses, serious damaging diseases caused by parasites such as Ichthyophthirius or the symptom of infection of Ichthyophthirius multiphilis, which is a kind of ciliate, and scuticociliatoisis by Scuticociliatida are also present. In Japan, a study on formalin digestion method, which is often used as a prevention method of parasitic diseases has been conducted. However, in the case of exposed imagoes, application to cultivation site, which was based on the report (Yoshinaga, T. and Nakazoe, J. 1993. Isolation and in vitro cultivation of an unidentified ciliate causing scuticociliatoisis in Japanese flounder, Fish Pathol., 28; 131) that the activity at digestion concentration of around 100 ppm was decreased, has shown that the experimental result showing no effect at all, is hard to be applied to (Mizuno, Y., 1993. Control methods of diseased flounder used in fish farm in Japan, J. Fish Pathol., 6; 219). This was carried out by the infectious disease prevention team of the cultivation site. Scutica proliferation method using cell culture method in the laboratory was a successful and confirmed pathogenicity thereof by applying to a flatfish using Scuticociliatida on cell culture. Removing the activity of imagoes by using Frezil and Actecin as a method for inactivation thereof in vitro was also a success, but there has not been any studies on inactivating infectious imagoes within the fish body (Yoshimizu, M., Hyuuga, S., Oh, M.-J., Ikoma, M., Kimura, T., Mori, T., Nomura, T., and Ezura, Y. 1993. Scuticociliatida infection of cultured hirame-characteristics, drug sensitivity and pathogenicity of cultured scuticocilliatida, J. Fish Pathol., 6; 205). There has not been any effects, as a result of the test for treatment effects using cultivating flatfish, fry and intermediary rearing fish in Korea and in the same manner of the study of Mizuno (Mizuno, Y., 1993. Control methods of diseased flounder used in fish farm in Japan, J. Fish Pathol., 6; 219) and Yoshimizu (Yoshimizu, M., Hyuuga, S., Oh, M.-J., Ikoma, M., Kimura, T., Mori, T., Nomura, T., and Ezura, Y. 1993. Scuticociliatida infection of cultured hirame-characteristics, drug sensitivity and pathogenicity of cultured scuticocilliatida, J. Fish Pathol., 6; 205) as the reason showing no treatment effect within the body, it is possible to remove Scutica exposed to the basin system same as in the case of formalin treatment. However, it has shown that it's not effective since a series of experimental drugs could not permeate into the body. It is not economical compared with cheap formalin in case of removing only discharged imagoes, because the price of the drug is much higher than that of general marine drugs. Pathological study by infection of parasite has been conducted in Korea (Lee, H.-S. and Sinskey, A. J. 1994. Molecular characterization of aceB, a gene encoding malate synthase in Corynebacterium glutamicum, J. Microbiol. Biotechnol., 4; 256) and it has shown that infection of imagoes causes fatal damage by passing through the epidermis and branchiae along the blood flow and attacking the nervous system within the body. This pathological phenomenon is similar to the result of studies on fry of flatfish (Cheung, R. J., Nigrelli, R. F. and Ruggieri, G. D. 1980. Studies on the morphology of uronema with a description of the infection in marine fish, J. Fish Disease, 3; 295) and freshwater fish (Hoffman, G. L. 1955. A disease of freshwater fish caused by tetrahymena and a key for identification of holotrich ciliates of freshwater fish, J. Parasitol., 61; 217).
Recently, with the rise of the problem of environmental pollution resulting from toxicity by overuse of chemical synthetic insecticide and herbicide, there has been a need for finding biological, particularly, microorganism-originated new materials. In light of this, δ-aminolevulinic acid has widely reported as biosynthetic precursors of tetrapyrrole compounds such as heme, bacteriochlorophyll, corrinoid, as photodynamic material which is the only known biological material, as herbicide, insecticide, plant growth stimulator and cancer cure (Hua, Z., Scott, L. G., Thomas, H. F., and Russell, H., 1995, Effectiveness of delta-aminolevulinic acid induced protoporphyrin as a photosensitizer for photodynamic therapy in Vivo, Cancer Research, 55; 1723; Matsumoto, T. H., Usui, K., and Ishizuka, K. 1992, Basis of Differential Tolerance of Plant Species to delta-Aminolevulinic Acid, Weed Research, 37; 60; Matsumoto, H., Tanida, Y., and Ishizuka, K. 1994. Porphyrin Intermediate Involved in Herbicidal Action of delta-Aminolevulinic Acid on Duckweed, Pesticide Biochemistry, 48; 214; Rebeiz, C. A, Juvik, J. A., and Reibez, C. C. 1988. Porphyric insecticides: Concept and phenomenology, Pestic. Biochem. Physiol., 30; 11; Tanaka, T., Takahashi, K., Hotta, Y., Takeuchi, Y., and Konnai, M., 1992. 5-aminolevulinic acid as plant growth stimulator, Eur. Pat. Appl. EP514 776). Also, δ-aminolevulinic acid has been regarded as an eco-friendly herbicide and insecticide because it is easily biodegradable. However, the quantity of δ-aminolevulinic acid produced in microorganism has low concentration and the industrialization of chemical synthetic production is also difficult owing to the complicated synthetic process (Beale, S. I., Gold, M. H., and Granick, S., 1979, Chemical synthesis of 4,5-dioxavaleric acid and its non-enzymatic transamination to 5-aminolevulinic acid, Phytochemistry, 18; 441). Therefore, highly toxic synthetic photodynamic herbicides, such as diphenyl ethers (DPEs) and oxadiazole are being produced by chemical synthesis. The problem of environmental pollution has brought up the harmfulness of these synthetic photodynamic herbicides. For example, contamination of water supply sources and damage of neighbors resulting from the overuse of herbicide in golf links have been raised as a social issue.
Once δ-aminolevulinic acid, which is specifically produced from Rhodobacter, is sprayed on plants, it acts on only dicotyledon selectively and then pchlide, strong oxidizing material, is formed through sunlight. Therefore, a series of oxidation reactions take place and lead to weed-killing activity, which destroys phospholipid of leaves and causes them to wither. Therefore, δ-aminolevulinic acid does not damage people, animal nor crop, only withering weeds selectively (Rebeiz, C. A., Montazer-Zouhoor, A., Hopen, H., and Wu, S. M., 1984. Photodynamic herbicides. Concept and phenomology, Enzyme Microb. Technol., 6; 390) and has been reported as eco-friendly herbicides (Rebeiz, C. A, Juvik, J. A., and Reibez, C. C. 1988. Porphyric insecticides: Concept and phenomenology, Pestic. Biochem. Physiol., 30; 11). However, δ-aminolevulinic acid is unprofitable since organic synthesis requires a complicated multi-step processes and the unit cost of production is high. Most of herbicides used currently have problems such as high toxicity to humans and high soil-toxicity (Beale, S. I., Gold, M. H., and Granick, S., 1979, Chemical synthesis of 42,5-dioxavaleric acid and its non-enzymatic transamination to 5-aminolevulinic acid, Phytochemistry, 18; 441).
The importance of food had been traditionally considered as a sequence of nutrition, flavor and safety. However, with the interests in increasing the national income and health, food safety has moved to the forefront. In regards to food safety, the pathogenic microorganism contaminated or mixed in foods, heavy metals, agricultural chemicals and antibiotics are most frequently raised. In case of cultivating fish, antibiotics remaining within the tissue of fishes, which resulted from over-administration, may decrease food safety. Pathogenic diseases occur frequently in accordance with the coastal contamination and congested nurseries. Due to rash administration of drugs in order to cure these diseases, new pathogenic microorganism having new drug-tolerance will appear and consequently, the development of new antibiotic is in high demand. To cure fishery diseases, as in medical science, development of more varied antibiotics can improve the productivity of cultivating fish but it may cause problems in the matter of food safety. Therefore, from seedling production nursery of cultivating fish to adult fish nursery, there is demanded for the development of new materials, which can widely prevent or cure diseases caused by pathogenic microorganisms.